Refrigerators and freezers typically obtain their cooling power from fluids that are harmful to the environment.
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A new type of crystal could allow refrigerators and air conditioners to keep us cool without warming the planet.
Refrigerators and air conditioners obtain their cooling power by circulating liquid through the unit. This device absorbs heat and causes cooling through a cycle of evaporation and condensation. However, many of those liquids contribute to the greenhouse effect, causing further warming if they leak. now, Jenny Pringle Australia’s Deakin University and her colleagues have used “plastic crystals” to create a climate-friendly alternative to these liquids. These are crystals with molecules that can move just enough to make them flexible.
If enough pressure is applied, these plastic crystals can deform. Their molecules range from being arranged randomly to neat grids. Then, when the pressure is removed, it becomes chaotic again. As part of this chaotic process, the crystals absorb heat, effectively cooling their surroundings.
This pressure-based cooling has been studied before, but most materials capable of making this transition can only do so at mild temperatures, which limits their cooling capabilities, Pringle says. In contrast, her team’s crystal’s heat-drawing ability begins at temperatures between -37°C (-34.6°F) and 10°C (50°F), a temperature range suitable for home refrigerators and freezers.
But the new crystals aren’t ready to leave the lab just yet. This is because the pressure required to operate them is very high. That’s hundreds of times higher than atmospheric pressure and thousands of meters underwater, Pringle says.
David Baldrin Researchers from the University of Glasgow, UK, said substances like those included in the new study “have the potential to almost completely decarbonize this massive scale.” [cooling] industry”, but he shares concerns about the high pressure required.
He says there may be another practical problem with this approach. living From the Chinese Academy of Sciences. With each repeated use, each crystal can absorb less heat as the lattice the molecules form becomes more strained. Nonetheless, Li said he was optimistic and confident the technology could be applied in the “near future.”
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